Hair straightener



FIG. 1 is a front, right side, top perspective view of a hair straightener showing my new design;

FIG. 2 is a rear, left side, bottom perspective view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a right side elevational view thereof;

FIG. 7 is a top plan view thereof;

FIG. 8 is a bottom plan view thereof; and,

FIG. 9 is a right side, top perspective view thereof showing the hair straightener in an open position ready to be used.

The broken lines shown on the hand grip portion of the straightener illustrate a pattern that forms part of the claimed design. The broken line electrical connection elements illustrate the environment of the hair straightener and form no part of the claimed design. 

CLAIM The ornamental design for a hair straightener, as shown and described. 